Nanosensors for the detection of hydrogen peroxide

Prussian Blue (PB) deposited on a nanoelectrode is the basis for an amperometric hydrogen peroxide sensor. Carbon nanoelectrodes, fabricated from pyrolytic decomposition of butane within a quartz nanopipette, were electrochemically etched and PB was deposited in the formed nanocavity. This procedure significantly increased the stability of PB films while maintaining a high mean sensitivity of 50 A mol− 1 l cm− 2 for H2O2 detection at − 50 mV vs. Ag/AgCl (0.1 M Cl−) at neutral pH value. Hydrogen peroxide was selectively quantified in the concentration range from 10 μM to 3 mM. We envision the application of these nanosensors to the intracellular monitoring of oxidative stress in living cells.